Script for populating html elements with content from a .json file not working on mobile

On THIS page I have a bunch of "placeholders" for phone numbers in the form: 07xxxxxxxx. Upon clicking the green button "VEZI TELEFON", the placeholder in each green box is replaced with a real phone number from a JSON file, via $.ajax.

The script works well on desktops and laptops, but, on mobile phones the first placeholder is not replaced. The same happens on the details page, where there is only one placeholder.